the government is tracking the activity trying to prevent from it becoming a full scale financial nightmare. tonight pierre thomas on who is behind it and what it means for your money. >> tonight the financial banking industry is on high alert. massive cyberattack remains under way. potentially millions of customers trying to bank on line this week blocked. among the target bank of america. p nc wells fargo oychlt there is elevated level of threat. threat is now high. >>reporter: sources tell the us it's denial of service attack. where hacker from the middle east have secretly taken thousands of computers worldwide. those computers zombie overwhelmed bank web site with barrage of traffic. different bank targeted on different days. today was p nc turn. >> we tried for 3 hours to get on p nc web site but we couldn't get through. >>reporter: facebook today frustrated customers. cynthia wrote time to you pay bills. this is ridiculous. the hopefully up soon. never realize how dependent i am on it. group of hacker warned the financial industry it was going to attack in retaliation for the controv